As Internet usage grows exponentially, the demand for Internet-related services is also growing rapidly. As a result of the increased usage of the Internet, the demand for domain names is also growing rapidly. Consequently, demand for domain related services is also on the rise. Such domain related services can include domain name creation, domain name registration renewal, and the like. Typically, a website serves as a primary vehicle for establishing an online presence for a domain name. To meet this ever increasing demand for domain name related services, it is necessary that the entities that provide these services do so in an efficient and cost-effective manner.
The Domain Name System (“DNS”) is the part of the Internet infrastructure that translates human-readable domain names into the Internet Protocol (“IP”) numbers needed to establish TCP/IP communication over the Internet. DNS allows users to refer to web sites, and other resources, using easier to remember domain names, such as “www.example.com”, rather than the numeric IP addresses associated with a website, e.g., 123.4.56.78, and assigned to computers on the Internet. Each domain name can be made up of a series of character strings (e.g., labels) separated by dots. The right-most label in a domain name is known as the top-level domain (“TLD”). Examples of well-known TLDs are “com”; “net”; “org”; and the like. Each TLD supports second-level domains, listed immediately to the left of the TLD, e.g., the “example” level in “www.example.com”. Each second-level domain can include a number of third-level domains located immediately to the left of the second-level domain, e.g., the “www” level in www.example.com.
The responsibility for operating each TLD, including maintaining a registry of the second-level domains within the TLD, is delegated to a particular organization, known as a domain name registry (“registry”). The registry is primarily responsible for answering queries for IP addresses associated with domains (“resolving”), typically through DNS servers that maintain such information in large databases, and for operating its top-level domain.
For most TLDs, in order to obtain a domain name, that domain name has to be registered with a registry through a domain name registrar, an entity authorized to register Internet domain names on behalf end-users. Alternatively, an end-user can register a domain name indirectly through one or more layers of resellers. A registry may receive registrations from hundreds of registrars.
A registrar usually has a dedicated service connection with the registries in order to access domain related services, e.g., domain name creation or renewal. Registrars typically use the Extensible Provisioning Protocol (“EPP”) as a vehicle to communicate with the registries in order to register or renew domain names. EPP is a protocol designed for allocating objects within registries over the Internet. The EPP protocol is based on Extensible Markup Language (“XML”), which is a structured, text-based format. The underlying network transport is not fixed, although the currently specified method is over Transmission Control Protocol (“TCP”).
A zone file is a text file that describes a portion of the DNS called a DNS zone. A zone file is organized in the form of resource records (RR) and contains information that defines mappings between domain names and IP addresses and other resources. The format of zone files is defined by a standard, with each line typically defining a single resource record. A line begins with a domain name, but if left blank, defaults to the previously defined domain name. Following the domain name is the time to live (TTL), the class (which is almost always “IN” for “internet” and rarely included), the type of resource record (A, MX, SOA, etc.), followed by type-specific data, such as the IPv4 address for A records. Comments can be included by using a semi-colon. There are also file directives that are marked with a keyword starting with a dollar sign.
The DNS distributes the responsibility of assigning domain names and mapping those names to IP addresses by designating authoritative name servers for each domain. Authoritative name servers are assigned to be responsible for their particular domains, and in turn can assign other authoritative name servers for their sub-domains. This mechanism generally helps avoid the need for a single central register to be continually consulted and updated. The DNS resolution process allows for users to be directed to a desired domain by a lookup process whereby the user enters the desired domain, and the DNS returns appropriate IP numbers. During the DNS resolution process, a request for a given domain name is routed from a resolver (e.g., a stub resolver) to an appropriate server (e.g., a recursive resolver) to retrieve the IP address. To improve efficiency, reduce DNS traffic across the Internet, and increase performance in end-user applications, the DNS supports DNS cache servers that store DNS query results for a period of time determined by the time-to-live (TTL) of the domain name record in question. Typically, such caching DNS servers, also called DNS caches, also implement the recursive algorithm necessary to resolve a given name starting with the DNS root through to the authoritative name servers of the queried domain. Internet service providers (ISPs) typically provide recursive and caching DNS servers for their customers. In addition, home networking routers may implement DNS caches and proxies to improve efficiency in the local network.
It may be desirable to maintain multiple name servers for a domain name for many reasons, including fault tolerance, load balancing, and geographical load distribution. There exists a large number of domains that perform frequent name server switches, even across several service providers. This phenomenon of name server switching is not usually expected under normal circumstances because it demands interference with existing DNS services. Additionally, domain names that perform frequent name server switches tend to be associated with objectionable behavior.
Accordingly, there is a need for methods, systems, and computer readable media for characterizing domain names based on name server switches.